New answers tagged windows-networking
Install your own DNS server on the Ubuntu server. The Ubuntu Server Guide has a chapter on DNS. Configure your DNS server as authoritative for your Active Directory Domain. Configure the department's DNS servers as forwarders.
Install your Windows domain as usual and point the clients to the Windows domain's DNS server, and set the department's DNS servers as forwarders in the Windows DNS server. The manual to do that: http://technet.microsoft.com/en-us/library/cc754941.aspx
As the message in the screenshot states, the problem is that there is another connection to the same server from the same client, but with a different username. Windows does not support that. So, if you are supposed to have access to those default (c$, d$, ...) shares (which requires an administrator account on the remote computer), you have to connect with ...
I might try turning windows firewall on and see if you can ping it. I've seen strange settings where it is turned off, but is still having an effect on a server.
Timed out. Never got an answer that worked, but this was way too long ago to find one now. Thanks for everyone who tried to help.
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